【摘要】 柴达木盆地三湖地区是中国陆上的大气田之一,产层位于第四系,储层疏松,气层埋藏浅。以往地震资料的信噪比和分辨率较低,难以识别地震含气异常。本文介绍一套适用于疏松砂岩区地震采集方法,包括小道距、高覆盖次数观测、精细表层调查及建模、优选岩性激发、数字检波器接收和折射静校正等技术。应用这套系列技术,采集到高信噪比、高分辨率、高保真度地震资料,较好地消除了近地表异常引起的地震异常,取得了高精度地震资料解释成果。更多还原

【Abstract】 Sanhu area in Qaidam Basin is the fourth largest land gas field in China.Gas reservoirs are buried in shallow Quaternary strata,and are characterized by unconsolidated medium and weak diagenesis.Seismic data obtained by the traditional seismic acquisition has some disadvantages:① Low signal-to-noise ratio and low resolution data cannot meet the requirements of natural gas explo-ration ;② Because of the shallow target formation,it is difficult to recognize abnormality caused by near-surface or gas-bearing layers.This paper introduces a series of high-density seismic acquisition methods,including high-density geometry design,optimized shooting,digital geophone receiving,accurate near-surface structure survey,and high-precision refraction static correction in this area.Application results show that seismic data with the characteristics of high signal-to-noise ratio,high resolution and high fidelity can be obtained using the proposed seismic acquisition technologies.As a result of decreasing the near-surface abnormality,seismic data interpretation precision is significantly improved.更多还原